Game Informer Online is reporting that Half-Life 2: Episode One will be released on May 31st. Thanks: Blues. In Episode One, player reprises his role of Dr. Gordon Freeman, who must immediately face the repercussions of his actions in City 17 and the Citadel. Freeman reconnects with Alyx Vance and her robot, Dog, as they continue their support of the resistance's battle against the Combine forces. Priced $19.99, Half-Life 2: Episode One, will not require Half-Life 2 to play and will offer four to six hours of gameplay.